1. Field of the Invention
Embodiments of the invention generally relate to a fluid leakage containment apparatus for use with fittings used to couple fluid lines.
2. Background of the Related Art
It is generally undesirable for fluids to escape from their containers or conduits and enter into the surrounding environment. This is particularly true in the semiconductor manufacturing industry where the fluids used during integrated circuit fabrication are expensive and/or may pose a serious threat to the environment and operators who may come in contact with released fluid. Examples of such fluids include chlorine, ammonia, hydrofluoric acid and chlorine, among many others.
In a typical semiconductor processing system, fluids are delivered to a processing chamber through conduits coupled to a gas panel. The gas panel generally controls the sequence, pressure and rate that various fluids are delivered to the processing chamber. Typically, fluids are supplied to the gas panel from vessels or the processing facility""s central supply. Generally, when one of the fluids being transferred between the gas panel and the process chamber poses a safety or environmental threat, the fluid lines, valves and/or fittings are equipped with a containment apparatus to prevent any leaking fluid from entering the environment.
For example, one example of a conventional containment apparatus is described in U.S. Pat. No. 6,298,881, issued Oct. 9, 2001 to Curran et al. Curran et al. generally describes a valve having a primary seal for retaining working fluids and a containment seal that circumscribes the primary seal. The containment seal is generally an elastomer compressed to seal the valve components. A vacuum source is coupled to a volume defined between the primary and containment seals to remove any working fluid that may have leaked beyond the primary seal.
However, containment seals utilized on these conventional containment apparatus are subject to damage during installation and wear over time. Additionally, as containment seals are exposed to corrosive or other reactive fluids over time, the seals may swell, shrink, crack, become brittle or otherwise exhibit some change in physical property that diminishes the effectiveness of the seal, thus creating a loss of vacuum and a potential leak path for the fluid to enter the environment defeating the containment apparatus.
Therefore, there is a need for an improved containment apparatus.
A method and apparatus for preventing leakage from a fitting coupling a first and second fluid supply line to an environment surrounding the fitting is generally provided. In one embodiment, a containment apparatus includes a body having a first, second and third aperture formed therethrough. The body defines an interior volume that is adapted to substantially enclose the fitting. The interior volume is adapted to be maintained at a pressure less than the surrounding environment to prevent fluids that may leak from the fitting from being released into the surrounding environment.
In another embodiment, a containment apparatus includes a first shell and a second shell that define a volume adapted to enclose the fitting. Each shell has an abutment surface that is disposed against the abutment surface of the other shell. The adjoining abutment surfaces define a gas permeable parting line. A first, second and third aperture are formed at least partially in the first or second shells. The apertures are adapted to facilitate routing fluid lines coupled to the fitting and coupling the containment apparatus to a vacuum source. In another embodiment, a containment apparatus prevents leakage from a fitting coupling a gas panel to a semiconductor processing chamber from reaching the surrounding environment.
In another aspect of the invention, a method for preventing fluid leakage from a fitting coupling a first and second conduit from entering an environment surrounding the fitting includes the steps of enclosing the fitting in a volume defined between a first shell and a second shell, evacuating the volume, and drawing air from the surrounding environment into the volume from between the shells.